Power tool with drop arm orbit bracket

• US 9,868,167 B2
• Filed: 03/04/2016
• Issued: 01/16/2018
• Est. Priority Date: 03/12/2015
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH, Robert Bosch Tool Corporation (Robert Bosch GmbH)
• Original Assignee: Robert Bosch GmbH, Robert Bosch Tool Corporation (Robert Bosch GmbH)
• Inventors: Doumani, Robert S., Laliberte, Eric, Szweda, Timothy, Taylor, Brian
• Primary Examiner(s): Michalski, Sean
• Application Number:
  US15/060,796
• Publication Number:
  US 20160263683A1
• Time in Patent Office: 683 Days
• Field of Search: 834772
• CPC Class Codes: B23D 45/067 the saw blade being adjustable according to depth or angle of cut
• CPC Class Codes: B23D 47/08 of devices for bringing the circular saw blade to the workpiece or removing same therefrom
• CPC Class Codes: B23D 59/002 for the position of the saw blade B27B5/36 and B27B9/02 take precedence
• CPC Class Codes: B27G 19/02 for circular saws

Abstract

A power tool assembly includes a drop arm assembly including a drop arm frame and an arbor shaft configured to support a shaping device at least partially above a workpiece support surface, the drop arm assembly configured to move within a drop plane to drop the shaping device completely beneath the workpiece support surface, a belt operably connected to the arbor shaft and configured to rotate the arbor shaft through a slave pulley, the slave pulley having a slave pulley axis of rotation, a motor including a power shaft operably connected to the belt through a motor end pulley, the motor end pulley having a motor end pulley axis of rotation, and an orbit bracket configured to orbitally support the drop arm assembly, the orbit bracket defining a drop arm orbit axis located between the motor end pulley axis of rotation and the slave pulley axis of rotation.

Claims

1. A power tool assembly, comprising:

a workpiece support surface;

a drop arm assembly including a drop arm frame and an arbor shaft configured to support a shaping device at least partially above the workpiece support surface, the drop arm assembly configured to move within a drop plane to drop the shaping device completely beneath the workpiece support surface;

a belt operably connected to the arbor shaft and configured to rotate the arbor shaft through a slave pulley, the slave pulley having a slave pulley axis of rotation;

a motor including a power shaft operably connected to the belt through a motor end pulley, the motor end pulley having a motor end pulley axis of rotation; and

an orbit bracket configured to orbitally support the drop arm assembly, the orbit bracket defining a drop arm orbit axis located between the motor end pulley axis of rotation and the slave pulley axis of rotation.

2. The power tool assembly of claim 1, wherein the drop arm orbit axis is lower than the motor end pulley axis of rotation.

3. The power tool assembly of claim 2, wherein the orbit bracket is fixedly attached to a height adjust carriage.

4. The power tool assembly of claim 3, wherein:

the height adjust carriage includes a locator pin and an anti-rotation pin;

the orbit bracket includes an alignment bore defining a bore axis and configured to receive the locator pin, and an anti-rotation slot extending lengthwise along a slot axis and configured to receive the anti-rotation pin; and

the slot axis is aligned to intersect the bore axis.

5. The power tool assembly of claim 4, wherein:

the orbit bracket includes an inner face portion configured to contact the height adjust carriage; and

the inner face defines a non-zero angle with respect to a plane parallel to the drop plane.

6. The power tool assembly of claim 5, wherein:

the inner face defines an angle of about 0.65°

with respect to a plane parallel to the drop plane.

7. The power tool assembly of claim 5, wherein:

the orbit bracket includes an orbit shaft hole through which an orbit shaft is inserted;

the drop arm frame is orbitally supported by the orbit bracket though the orbit shaft; and

the orbit shaft hole includes a lower portion and an upper portion, the lower portion and the upper portion configured to form two shoulders extending within the orbit shaft hole along an axis defined by the orbit shaft hole.

8. The power tool assembly of claim 7, wherein:

the lower portion is a lower circular portion having a first origin;

the upper portion is an upper circular portion having a second origin; and

the second origin is offset from the first origin.

9. The power tool assembly of claim 7, wherein:

the lower portion is a lower circular portion having a first diameter size;

the upper portion is an upper circular portion having a second diameter size; and

the second diameter size is different from the first diameter size.

10. The power tool assembly of claim 7, further comprising:

at least two set screws, each of the at least two set screws configured to force the orbit shaft against the two shoulders.

11. The power tool assembly of claim 10, wherein:

the orbit bracket further includes a pair of aligned bores opening to the orbit shaft hole;

the orbit shaft includes an orbit shaft bore passing therethrough and aligned with the pair of aligned bores; and

the power tool assembly further includes an orbit pin extending through the pair of aligned bores and the orbit shaft bore.

12. A method of connecting a drop arm assembly of a power tool assembly, the drop arm assembly including a drop arm frame and an arbor shaft configured to support a shaping device at least partially above a workpiece support surface, the drop arm assembly configured to move within a drop plane to drop the shaping device completely beneath the workpiece support surface, comprising:

defining a slave pulley axis of rotation for a slave pulley configured to be rotated by a belt;

defining a motor end pulley axis of rotation for a motor end pulley configured to be operably connected to a power shaft of a motor, and configured to be operably connected to the belt; and

defining a drop arm orbit axis located between the motor end pulley axis of rotation and the slave pulley axis of rotation with an orbit bracket configured to orbitally support the drop arm assembly.

13. The method of claim 12, wherein defining the drop arm orbit axis comprises defining a drop arm orbit axis that is lower than the motor end pulley axis of rotation.

14. The method of claim 13, wherein defining the drop arm orbit axis comprises fixedly attaching the orbit bracket to a height adjust carriage.

15. The method of claim 14, wherein fixedly attaching the orbit bracket to a height adjust carriage comprises:

inserting a locator pin of the height adjust carriage into an alignment bore of the orbit bracket, the alignment bore defining a bore axis; and

inserting an anti-rotation pin of the height adjust carriage into an anti-rotation slot of the orbit bracket, the anti-rotation slot including a slot axis extending lengthwise along the slot, the slot axis aligned to intersect the bore axis.

16. The method of claim 15, wherein fixedly attaching the orbit bracket to the height adjust carriage comprises:

positioning an inner face portion of the orbit bracket against the height adjust carriage, the inner face defining a non-zero angle with respect to a plane parallel to the drop plane.

17. The method of claim 15, wherein defining the drop arm orbit axis comprises:

inserting an orbit shaft within an orbit shaft hole of the orbit bracket; and

contacting two shoulders, extending along an axis defined by the orbit shaft hole and defined by a lower portion and an upper portion of the orbit shaft hole, with the inserted orbit shaft.

18. The method of claim 15, wherein defining the drop arm orbit axis comprises:

forcing the orbit shaft against the two shoulders with at least two set screws.

19. The method of claim 18, further comprising:

aligning an orbit shaft bore with a pair of aligned bores opening to the orbit shaft hole; and

positioning an orbit pin through the pair of aligned bores and the aligned orbit shaft bore.

20. The method of claim 19, further comprising:

compressing a pair of bearings against respective inner bearing walls of spaced apart brackets of the drop arm frame using the orbit shaft.